Thomas maxon



(No Model.) i

T. MAXON.

LIPTING JACK.

WWII- .dtzforney N. PETERS, Phalmliihnguph nnnnnnnnn n n NI-TED STATES THOMAS MAXON, OF DAYTON, OHIO, ASSIGNOR 0F ONE-HALF TO J. V.

CARPENTER, OF SAME PLACE.

LlFTlNG -JACK.

SPECIFICATION forming part of Letters Patent No. 395,161, dated December 25, 1888.

Application filed May 4:, 1888. $erial No. 272,751. (No model.)

To all whom it may concern:

Be it known that I, THOMAS MAXON, a citizen of the United States, residing at Dayton, in the county of Montgomery and State of Ohio, have invented certain new and useful Improvements in Lifting-Jacks, of which the following is a specification, reference being had therein to the accompanying drawings.

My invention relates to certain new and useful improvements in lifting-jacks, and the object I have in viewis to provide a light, strong, and durable jack, which at the same time will be rapid and positive in operation and complete in all its details of construction, as will be more fully hereinafter set forth.

The invention consists in certain novel features of construction and arrangements of parts, that will be fully hereinafter described, and particularly pointed out in the claims appended.

I Referring to the accompanying drawings, which form a part of this specification, Figure 1 represents a vertical sectional view of my improved jack complete; Fig. 2, a detail vertical sectional view of the standard, and

Fig. 3 a detail side elevation of the liftingdog.

Referring to the drawings by letters, A designates the hollow stamlard of the jack, which is preferably cast in a single piece and provided with a suitable base, Ill. In suitable ways formed in this hollow standard is arranged to work the lifting-bar C, provided on its rear side with the usual teeth or serrations, and on its front side, at its lower end, with the lifting-foot I), which latter projects through a vertical slot in the front side of the standard and rests in a suitable recess in the base B when the bar is down. This liftingbar and its foot are cast hollow, as shown. Passed vertically through the bar is a strengthening-bolt, E, the head a of which is countersunk in the lower end of the lifting-bar, and its upper screw-threaded end projects a little above the upper end of the same, andis there provided with nut, F, this nut serving also as a cap-piece for the lifting-bar. By making the lifting-bar and its foot hollow a saving of metal is not only effected, but the bar ismade much stronger, as the metal has a better opportunity to become more thoroughly annealed.

Pivotally supported in the usual. swinging links, G, (only one of which shown,) hung upon the end of a transverse bolt, Ill, is the operating-lever I, which has pivoted to its inner end the lifting-dog J, provided with teeth on its lower portion to engage the teeth on the lifting-bar.

The upper end of the lifting-dog J provided with a transverse pin, K, which works in vertical slots L, formed in the sides of the standard, and its lower end is beveled at l), for

a purpose that will presently appear. Immediately ever the upper end of the dogJ' is a cap, M, which is cast integral with the standard and serves to assist in restricting the upward movement of the said dog .I. Pivoted upon the transverse bolt H between the sides of the standard is a spring-actuated retaining-pawl, N, which engages the teeth of the lifting-bar and holds it at any desired point. Pivoted to the outer end of this pawl is a depending catch, 0, which is hooked under the lower edge of the cap M when it is desired to hold the pawl out of engagement with the lifting-bar. This pawl is held normallyin. engagement with the lifting-bar by means of a Hat spring, N, the free end of which bears upon the upper rounded surface of the cap M. l-ly operating the lever I it is evident the teeth on the lower portion of the dog J will engage with the lifting-bar and elevate the same, the pawl N serving to hold the bar at any desired height, and the pin K serving both as a pivot and guide for the dog, allowingit to be swung out of engagement with the lifting-bar at every upward movement of the handle of the operating-lever, as is evident.

\Vhen it is desired to drop the lifting-bar, the pawl N is first disengaged and held out of engagement by means of the catch 0. The handle of the operating-lever is then. elevated, permitting the lifting-bar with the engaged dog to move downward. The dog continues in engagement with. the lifting-bar until its lower beveled end, Z), strikes against the beveled lip Z) of the standard, and the pin K reaches the lower outwardly-inclined portions, L, of the slots L,when it is automatically disengaged, these beveled portions and slots serving to throw the dog bodily out of engage ment.

To prevent the dogJ from swinging too far out from the lifting-bar when it is disengaged therefrom, I provide a cap or guard, P, which is preferably formed integral with the standard A, and is located immediately below the fplcrum of the operating-lever.

IL ving thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In a lifting-jack, the con'lbination, with the hollow standard A, provided with a cap, M, a beveled lip, b, and a guard, P, of the lifting-bar working in the standard A, the retaining-pawl N, provided with the depending catch 0, the sliding dog J, provided with a transverse pin, K, which works in slots L L in the standard, this dog having its lower end beveled at I), the operating-lever pivoted to the dog J, and the swinging links G for supporting this lever, substantially as herein described.

2. The combination of the hollow standard provided with the vertical slots L, having their lower ends, L, inclined outwardly, the liftingbar, the dog J, provided with a transverse pin, K, which works in said slots, and the operating-lever, substantially as described.

3. The combination of the hollow standard provided with the cap M, the lifting-bar, the dog and operating-lever, and the pivoted retaining-pawl N, provided with a catch, 0, all arranged substantially as described.

4:. A lifting-bar, O, provided with a lifting foot, D, both bar and foot being cast hollow, in combination with a headed and screwthreaded bolt, E, passed longitudinally -through the lifting-bar, the head of the bolt being countersunk in the lower end of the said bar, and a cap-piece, F, screwed on the upper projecting end of the said bolt E, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

THOMAS MAXON.

Witnesses:

JOHN L. H. FRANK, JAMES Q. CARTER. 

